If U.S. pulls out of Paris Climate Agreement

Earth is likely to hit more dangerous levels of warming even sooner if the US pulls back from its pledge to cut carbon dioxide pollution, scientists said. That’s because America contributes so much to rising temperatures.
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In an attempt to understand what could happen to the planet if the U.S. pulls out of Paris, The Associated Press consulted with more than two dozen climate scientists and analysed a special computer model scenario designed to calculate potential effects.

Scientists said it would worsen an already bad problem, and make it far more difficult to prevent crossing a dangerous global temperature threshold.